1. Field of the Invention
This invention relates generally to sleeping bags, and more particularly to a sleeping bag having a plurality of openings in the top cover that provide concurrent ingress/egress of selected parts of the user's body for selective coverage and exposure.
2. Background Art
Sleeping bags are used in a wide variety of wilderness applications, including rock and ice climbing, camping, backpacking, fishing, mountain climbing, etc. These activities are carried on throughout the year in a range of climatic regions and weather conditions.
Conventional rectangular sleeping bags are configured into a shell having a bottom portion or panel upon which a user occupying the sleeping bag lays and a top portion or panel that extends over the user to cover the user. The top and bottom portions or panels of the shell may be formed by a single panel which is folded over itself and fastened together along the foot end and one side, such as by a zipper, or the top and bottom portions or panels may be individual panels fastened together with a peripheral zipper running along the foot end and both sides. When the top and bottom portions or panels of the sleeping bag are configured into a shell, their unfastened edges define an end opening at the head end that permit the user to extend his body into the interior space; or the user may enter the interior space by unzipping one side. Typically, the user is enclosed within the interior space with only his head extending out of the opening at the head end of the sleeping bag.
Conventional mummy type sleeping bags, which generally minimize internal volume, have a laterally tapered shell shaped approximately to the contour of the body with an enclosed head end that covers the user's head. Typically, a face opening is provided at the head end that exposes the user's face, and a zipper that extends longitudinally along the center of the sleeping bag from the face opening to the foot end of the bag.
The conventional sleeping bags are primarily constructed to enclose the user's entire body, with the exception of the head or face, and rely on the conservation of heat by decreasing air movement within the bag for thermal efficiency. Thus, most sleeping bags are well suited for use in outdoor, cold ambient temperatures, however, outdoor enthusiasts who wish to use a sleeping bag in both warm and cold environments presently are required to purchase a separate sleeping bag designed for each environment. Purchasing multiple sleeping bags is costly to the user and takes up storage space in the user's home.
Another problem with conventional rectangular and mummy style sleeping bags is their relatively small lateral dimension and snug fit significantly limits the user's range of motion which makes some users feel uncomfortable and confined. The feeling of discomfort is typically heightened if parts of the user's body that are often moved, especially during sleep, such as the shoulders, chest, arms, legs, knees, and feet, are confined.
Because they are primarily constructed to retain heat by preventing warm air from escaping, most conventional sleeping bags do not provide openings in the bag structure with the exception of the head or face openings. However, each person is different and conditions of both the individual and the environment differ at any given time. For example, some people tend to sleep cold, and others tend to sleep hot, and a user may feel warmer one night than another night.
Thus, due to the construction of the conventional sleeping bags, even sleeping bags particularly designed for warm or cold environments, there is no provision for allowing a user to selectively place various different parts of his or her body desired to be kept warm into the sleeping bag so as to be covered, while at the same time, extend other parts of their body desired to be cooled out of the sleeping bag, to provide individual selective temperature control and comfort to fit the user and environmental weather conditions.
There are several patents directed toward various sleeping bags, covers, and articles of clothing having an opening through which the user's head or feet head passes.
Peterson et al, U.S. Pat. No. 6,693,498), discloses a conventional sleeping bag which includes a top, a bottom, left and right edges extending along the sides, a head end, a foot end, and a zipper extending along the foot end the right edge.
Taylor, U.S. Pat. No. 2,888,009, discloses a generally rectangular infant's sleeping bag closed along all four sides for covering an infant from the neck down, that has a circular neck opening near one end through which the infant's head passes, a zipper fastener that extends longitudinally along the center of the sleeping bag from the neck opening toward the bottom end of the bag, and ties at the four corners of the bag for attaching the sleeping bag to portions of the crib, bed, or the like upon which it is placed.
Innes, U.S. Pat. No. 3,381,306, discloses a multipurpose blanket having a single zippered head opening and zippers along the laterally opposed sides, through which a user's head passes. The single head opening is disposed in the center of the blanket in an unfolded condition and at the top end (folded end) when the blanket is folded or supported on the user's shoulders. The folded blanket may be supported on the user's shoulders and worn like a serape, or may be worn as a dressing tent wherein the lateral sides are zipped closed, and when worn like a poncho, a portion of the back side of the folded blanket is supported on top of the user's head and the neck opening forms an oval shaped opening to be used as a face opening.
Garrigues, U.S. Pat. No. 5,881,405, discloses is a personal shelter in the form of a “bivy” sack or sleeping bag that has a first foot opening at the foot end and a second opening located near the head end. The user enters and exits the “bivy” sack through the head opening and thereafter it is used for ventilation and viewing. The foot opening is a foot vent defined by edges of a top piece and an end piece that allows stagnant air within the foot end of the bivy sack to escape and fresher outside air to enter. The head opening is covered by a removable mesh screen and a mesh screen is secured over the foot opening.
Maturaporn, U.S. Pat. No. 6,560,797, discloses a generally rectangular disposable blanket for covering the front of a user from the neck down that is formed of a plurality of overlapped cover sheets ultrasonically welded along all four side edges and has a positioning slit cut through the cover sheets through which the user passes his or her head so as to wear the disposable blanket on his or her neck such and maintain the position of the entire blanket on the user's body.
McCully et al, U.S. Published Application 20050051203 discloses a generally rectangular sheet for aiding survival during outdoor activities, and as a rescue apparatus in the event of an emergency, which is suitable for use as a sleeping bag, a blanket, a distress signal indicator, a stretcher, a water catcher, a hammock, a tent, a shelter or a poncho. The sheet opposed first and second surfaces, the first surface being adapted to surround a user's body when the sheet is in a folded state. When the sheet is in the folded state, the second surface is substantially bisected into upper and lower surfaces in use. The first surface is preferably brightly colored, and may also be fluorescent or luminescent and/or reflective. Additionally or alternatively, at least the upper surface of the bisected second surface is preferably brightly colored or may be fluorescent, luminescent and/or reflective.
Calutoiu, U.S. Pat. No. 4,507,805, discloses a generally rectangular convertible sleeping bag for use as a sleeping bag and an ambulatory garment that has an integral upper torso portion extending downward to the general location of the crotch, and a lower torso portion. The bag/garment has a front and back and similar to a convention sleeping bag, has outside zippers or fasteners that extend across the top and one side, respectively. A vertical convenience zipper in the crotch area in the front and a second vertical convenience zipper in the back are disposed centrally on the front and back of the structure. A pair of laterally spaced horizontal zippers are disposed on the front to provide openings through which the arms of the user can be extended. The head of the user can be extended through the unzipped top opening, and ingress and egress from the bag is possible through either the unzipped top opening or side. The front and back are also provided with vertical zipper elements spaced below the convenience zippers that can each be fastened to the zipper element on each side to create a pair of individual leg receiving portions, which are also provided with individual zippered openings at their respective lower extremities, through which the user can extend his feet to walk while the bag/garment is being worn.
Bull, U.S. Pat. No. 5,611,082, discloses two embodiments of thermally insulated outer garments for covering the head, torso, arms, and legs of the wearer or any portion thereof, and which also cover the feet of the wearer and the footwear on the feet of the wearer. In one embodiment the garment is similar to a pair of coveralls and has separate insulated leg and foot covering portions for each leg and foot with a reclosable opening on the back of the leg portions. The other embodiment is in the form of a body suit wherein the lower portion has a sleeping bag type configuration with a single insulated enclosure for both legs and both feet with a reclosable opening on the back of the lower portion that extend from the bottom of the leg and foot portion upward to the thigh portion so that the shoe and foot covering portions may be slipped off of the foot and secured onto the upper portion of the leg. The openings on the back of the leg portions allow the wearer to extend their legs outwardly through the back of the leg portions and permit the wearer to walk about while keeping the foot portion of the insulated garment out of contact with the ground and without removing any separate parts of the garment.
Miele, U.S. Pat. No. 4,215,435 discloses a pair of convertible trousers including a body portion configured to be placed on the lower half of a human torso in a conventional manner, a pair of leg portions for accommodating therein the legs of the wearer, the leg portions each comprising a plurality of flexible interchangeable tubular elements, and snap fasteners for selectively removably securing the flexible interchangeable tubular elements coextensively together. The tubular elements may be joined to the body portion in various configurations to produce a garment of a variable length which may be altered to present several different visual appearances.
Cha, U.S. Published Application 20060021140, discloses a bed covering having an opening across horizontally at about midpoint of the vertical length of the bed covering formed by a generous overlapping of an upper portion and a lower portion of the bed covering for allowing a part of a person's body (such as the feet) to exit to the outside of the bed covering. The bed covering is comprised of two generally rectangular panels of flexible material, each having a top edge, left edge, right edge, and bottom edge. The length of the rectangular upper panel is generally longer than the length of the rectangular lower panel, but could be shorter or equal to the length of the lower panel. The vertically spaced upper and lower panels are initially two separate pieces and are vertically joined by overlapping the bottom edge of the upper panel over the top edge of the lower panel and then permanently sewing the overlapped areas together only along the left and right sides to form a continuous one-piece bed covering. The overlapped panels define the horizontal opening extending between the overlapping areas, the mouth of which is formed between the inner overlapped layer and outer overlapping layer. The overlapped configuration of the opening only allows a person who is underneath the bed cover to extend one part of their body (such as the feet) outside of the bed covering.